Prolonged lifespan of initial-anode-free lithium-metal battery by pre-lithiation in Li-rich LiNiMnO spinel cathode.

Anode-free lithium metal batteries (AF-LMBs) can deliver the maximum energy density. However, achieving AF-LMBs with a long lifespan remains challenging because of the poor reversibility of Li plating/stripping on the anode. Here, coupled with a fluorine-containing electrolyte, we introduce a cathode pre-lithiation strategy to extend the lifespan of AF-LMBs.

Electrochemical characterization of and theoretical insight into a series of 2D MOFs, [M(bipy)(CO)(HO)]·3HO (M = Mn (1), Fe (2), Co (3) and Zn (4)), for chemical sensing applications.

The electrochemical sensing applications of a series of water-stable 2D metal-organic framework (MOF)-modified screen-printed carbon electrodes (SPCEs) are reported. The MOF materials in this study are [M(bipy)(CO)(HO)]·3HO, in which bipy = 4,4'-bipyridine and M = Mn, Fe, Co and Zn. The MOF materials are characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), showing that the MOFs have a layer-by-layer rod structure with a smooth surface.

The spin-orbit-phonon coupling and crystalline elasticity of LaCoO perovskite.

Based on an integrated study of magnetic susceptibility, specific heat, and thermal expansion of single-crystal LaCoO free from cobalt and oxygen vacancies, two narrow spin gaps are identified before and after the phonon softening of gap size Δ ∼ 0.5 meV in a CoO-octahedral crystal electric field (CEF) and the thermally activated spin gap ∼ 25 meV, respectively. Significant excitation of Co spins from a low-spin (LS) to a high-spin (HS) state is confirmed by the thermal activation behavior of spin susceptibility of energy gap ∼ 25 meV, which follows a two-level Boltzmann distribution to saturate at a level of 50% LS/50% HS statistically above ∼200 K, without the inclusion of a postulated intermediate spin (IS) state.

A new protocol for the preparation of superconducting KBi.

A superconducting KBi sample was successfully prepared using a liquid ammonia (NH) technique. The temperature dependence of the magnetic susceptibility (/) showed a superconducting transition temperature ( ) as high as 3.6 K.

Reduced Local Symmetry in Lithium Compound LiSrSiO Distinguished by an Eu Spectroscopy Probe.

Research on lithium compounds has attracted much attention nowadays. However, to elucidate the precise structure of lithium compounds is a challenge, especially when considering the small ions that may be transferred between the interstitial voids. Here, the discovery of reduced local symmetry (symmetry breaking) in small domains of LiSrSiO is reported by employing Eu as a spectroscopic probe, for which X-ray, neutron, and electron diffraction have confirmed the average long-range structure with the space group 321.

Novel Eu-activated thiogallate phosphors for white LED applications: structural and spectroscopic analysis.

Novel Eu-activated BaGaSiS and BaGaSiS thiogallate phosphors were prepared by solid-state reaction route. The BaGaSiS:Eu phosphor generated a green emission upon excitation at 405 nm, whereas the BaGaSiS:Eu phosphor could be tuned from cyan to green range with increasing Eu concentration upon excitation at 365 nm. Additionally, the thermal luminescence properties of the thiogallate phosphors were investigated in the temperature range of 25 to 250 °C.

Saturation and beating of acoustic phonon oscillations excited near the exciton resonance of strained polar ZnO/ZnMgO multiple quantum wells.

Saturation and beating of coherent acoustic phonon (CAP) oscillations were observed and attributed to the screening of a built-in electric field with increasing pump power using degenerate pump-probe measurements near the exciton resonance of polar ZnO/ZnMgO multiple quantum wells (MQWs). After purifying the CAP signals by using an empirical mode decomposition, we found not only that the CAP amplitude follows the trend of the band gap renormalization (BGR) and shows saturation at high pump power, but also that the CAP oscillation period coincides with that of the MQWs, consistent with the XRD and TEM results. An additional low-frequency oscillation modifying the CAP signal is revealed due to the negative change in refractive index caused by BGR as the pump power increases.

Non-Fermi Liquids as Highly Active Oxygen Evolution Reaction Catalysts.

The oxygen evolution reaction (OER) plays a key role in emerging energy conversion technologies such as rechargeable metal-air batteries, and direct solar water splitting. Herein, a remarkably low overpotential of ≈150 mV at 10 mA cm in alkaline solutions using one of the non-Fermi liquids, HgRuO, is reported. HgRuO displays a rapid increase in current density and excellent durability as an OER catalyst.